Tractor front loaders

Tractor front loaders

A track loader is an engineering vehicle consisting of a tracked chassis with a loader for digging and loading material. The history of track loaders can be defined by three evolutions of their design. Each of these evolutions made the track loader a more viable and versatile tool in the excavation industry. These machines are capable in nearly every task, but master of none. A dozer, excavator, or wheel loader will out perform a track loader under a set of conditions, but the ability of a track loader perform almost every task on a job site is why it remains a part of many companies' fleets.

The first track loaders were built from track tractors with scratch built loaders. The first loaders were cable operated like the bulldozers of the era. These track loaders lacked the ability to dig in hard ground, but so did the dozers of the day. They were mostly used for moving stockpiled material and loading trucks and rail cars.

The first major design change to track loaders came with the integration of hydraulic systems. Using hydraulics to power the loader linkages increased the power of the loader. More importantly, the loaders could apply down pressure to the bucket, vastly increasing their ability to dig unworked ground. Most of the track loaders were still based on a bulldozer equivalent. The weight of the engine was still on the front half of the tracks along with the heavy loader components. This caused many problems with heavy wear of the front idler wheels and the undercarriage in general. The Caterpillar 983 track loader, the second largest track loader ever built, was notorious for heavy undercarriage wear.

 

The hydrostatic drive system was the second major innovation to affect the design of track loaders.

Track loaders have become very sophisticated machines, using hydrostatic transmissions and electro-hydraulic controls to increase efficiency. Until the rise in popularity of excavators, track loaders had little competition digging and loading jobs.

Telescopic handler (telehandler)

Telescopic handler (telehandler)

  

A telescopic handler, or telehandler, is a machine widely used in agriculture and industry. It is similar in appearance and function to a forklift but is more a crane than forklift, with the increased versatility of a single telescopic boom that can extend forwards and upwards from the vehicle. On the end of the boom the operator can fit one of several attachments, such as a bucket, pallet forks, muck grab, or lift table.

The most common attachment for a tele-handler is pallet forks and the most common application is to move loads to and from places unreachable for a conventional forklift. For example, telehandlers have the ability to remove palletized cargo from within a trailer and to place loads on rooftops and other high places. The latter application would otherwise require a crane, which is not always practical or time-efficient.

The advantage of the telehandler is also its biggest limitation: as the boom extends or raises while bearing a load, it acts as a lever and causes the vehicle to become increasingly unstable, despite counterweights in the rear. This means that the lifting capacity quickly decreases as the working radius (distance between the front of the wheels and the centre of the load) increases. A vehicle with a 5,000lb capacity with the boom retracted may be able to safely lift as little as 400lb with it fully extended at a low boom angle. The same machine with a 5,000lb lift capacity with the boom retracted may be able to support as much as 10,000lb with the boom raised to 70°. The operator is equipped with a load chart which helps him determine whether a given task is possible, taking into account weight, boom angle and height. Failing this, most telehandlers utilize a computer which uses sensors to monitor the vehicle, and will warn the operator and/or cut off further control input if the limits of the vehicle are exceeded. Some machines are also equipped with front outriggers and can be called mobile cranes, which extend the lifting capability of the equipment while stationary.

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Skid loader

A skid loader or skid steer loader is a small rigid frame, engine-powered machine with lift arms used to attach a wide variety of labor-saving tools or attachments. Though sometimes they are equipped with tracks, skid-steer loaders are typically four-wheel drive vehicles with the left-side drive wheels independent of the right-side drive wheels. By having each side independent of the other, wheel speed and direction of rotation of the wheels determine the direction the loader will turn.

Operation

A Skid Steer loader can sometimes be used in place of a large excavator by digging a hole from the inside. The skid loader first digs a ramp leading to the edge of the desired excavation. It then uses the ramp to carry material out of the hole. The skid loader reshapes the ramp making it steeper and longer as the excavation deepens. This method is particularly useful for digging under a structure where overhead clearance does not allow for the boom of a large excavator, such as digging a basement under an existing house.

The conventional bucket of many skid loaders can be replaced with a variety of specialized buckets or attachments, many powered by the loader's hydraulic system. These include backhoe, hydraulic breaker, pallet forks, angle broom, sweeper, auger, mower, snow blower, stump grinder, tree spade, trencher, dumping hopper, ripper, tillers, grapple, tilt, roller, snow blade, wheel saw, cement mixer, and wood chipper machine.

Off-road dump truck

Off-road dump truck

 A dump truck is a truck used for transporting loose material (such as sand, gravel, or dirt) for construction. A typical dump truck is equipped with a hydraulically operated open-box bed hinged at the rear, the front of which can be lifted up to allow the contents to be deposited on the ground behind the truck at the site of delivery.

Off-road dump trucks more closely resemble heavy construction equipment or engineering vehicles than they do highway dump trucks. Off-road dump trucks are used strictly off-road for mining and heavy dirt hauling jobs. There are two primary forms: rigid frame and articulating frame.

The term ‘dump’ truck is not generally used by the mining industry, or by the manufacturers that build these machines.

Bottom dump normally describes a trailer that discharges its load by opening two clam shell doors under the load space. In some instances, one tractor may pull several trailers (road train).

Rear end/Rear dump trailers are especially effective for longer hauls (typically one mile or longer). Better tire load distribution resulting in increase in tire life. Savings in fuel, maintenance and operating costs. Short turning radius - highly maneuverable. Dump cylinders tip the body at a very high dump angle thus shedding the material in an efficient manner.

The current largest off road haul trucks are the Caterpillar 797F, which each have payload capacities of up to 400 short tons (363 t; 357 long tons). The Caterpillar 797 is unique in this class because it employs a diesel engine to power a mechanical powertrain typical of most road going vehicles.

Loader

Loader

 

A loader is a heavy equipment machine often used in construction, primarily used to load material (such as asphalt, demolition debris, dirt, snow, feed, gravel, logs, raw minerals, recycled material, rock, sand, and woodchips) into or onto another type of machinery (such as a dump truck, conveyor belt, feed-hopper, or railcar).

Heavy equipment front loaders

A loader is a type of tractor, usually wheeled, sometimes on tracks, that has a front mounted square wide bucket connected to the end of two booms (arms) to scoop up loose material from the ground, such as dirt, sand or gravel, and move it from one place to another without pushing the material across the ground. A loader is commonly used to move a stockpiled material from ground level and deposit it into an awaiting dump truck or into an open trench excavation.

The loader assembly may be a removable attachment or permanently mounted. Often the bucket can be replaced with other devices or tools—for example, many can mount forks to lift heavy pallets or shipping containers, and a hydraulically-opening "clamshell" bucket allows a loader to act as a light dozer or scraper. The bucket can also be augmented with devices like a bale grappler for handling large bales of hay or straw.

Large loaders, such as Caterpillar 950H, 966H usually have only a front bucket and are called Front Loaders, whereas small loader tractors are often also equipped with a small backhoe and are called backhoe loaders or loader backhoes.

Loaders are used mainly for uploading materials into trucks, laying pipe, clearing rubble, and digging. A loader is not the most efficient machine for digging as it cannot dig very deep below the level of its wheels, like a backhoe can. The capacity of a loader bucket can be anywhere from 0.5 to 36 m³ [1] depending upon the size of the machine and its application. The front loader's bucket capacity is generally much bigger than a bucket capacity of a backhoe loader.

Unlike most bulldozers, most loaders are wheeled and not tracked, although track loaders are common. They are successful where sharp edged materials in construction debris would damage rubber wheels, or where the ground is soft and muddy. Wheels provide better mobility and speed and do not damage paved roads as much as tracks, but provide less traction.

In construction areas loaders are also used to transport building materials - such as bricks, pipe, metal bars, and digging tools - over short distances.

High-tip buckets are suitable for light materials such as chip, peat and light gravel and when the bucket is emptied from a height.

Unlike backhoes or standard tractors fitted with a front bucket, many large loaders do not use automotive steering mechanisms. Instead, they steer by a hydraulically actuated pivot point set exactly between the front and rear axles. This is referred to as "articulated steering" and allows the front axle to be solid, allowing it to carry greater weight. Articulated steering provides better maneuverability for a given wheelbase. Since the front wheels and attachment rotate on the same axis, the operator is able to "steer" his load in an arc after positioning the machine, which can be useful. The tradeoff is that when the machine is "twisted" to one side and a heavy load is lifted high, it has a greater risk of turning over to the "wide" side.

Front loaders gained popularity during the last two decades, especially in urban engineering projects and small earthmoving works. Heavy equipment manufacturers offer a wide range of loader sizes and duties.

The term "loader" is also used in the debris removal field to describe the boom on a grapple truck.

Landfill compaction

Landfill compaction

A landfill compaction vehicle has two main functions: to spread the waste evenly in layers over the landfill and to compact waste to reduce its volume and help stabilize the landfill. Proper waste compacting includes the process of using a steel wheeled/drum landfill compactor to shred, tear and press together various items in the waste stream so they consume a minimal volume of landfill airspace. The higher the compaction rate, the more trash the landfill can receive and store. This will also reduce landslides, cave-ins and minimize the risk of fire.

Main compaction is produced by the landfill compactors steel tooth on the wheel drums. Special teeth can penetrate the waste and deliver a focused compression point, providing compaction and increased density. Ground pressure of the tooth can exceed over 4000 PSI. The design of the machine and more importantly the wheels and the teeth is very critical in compaction. The steel wheels should be as wide as possible and have as many teeth as possible. Small wheel only spreads the waste, but large compactor drum can compact, tear and shred the waste, creating a nice even compacted surface.

  Benefits of proper waste compaction in landfill:

• ·         Improved traffic flow and turnaround time
• ·         Reduced space and food for vermin
• ·         Improved control of water flows
• ·         Controlled gas production and minimizing of odors
• ·         Less cover soil required even surface
• ·         Minimized airborne debris

What is a Motor Grader

Motor grader

A motor grader, also commonly referred to as a road grader, a blade, or a maintainer, is a construction machine with a long blade used to create a flat surface. Typical models have three axles, with the engine and cab situated above the rear axles at one end of the vehicle and a third axle at the front end of the vehicle, with the blade in between. In certain countries, for example in Finland, almost every grader is equipped with a second blade that is placed in front of the front axle. Some construction personnel refer to the entire machine as "the blade."

In civil engineering, the motor grader's purpose is to "finish grade" (refine, set precisely) the "rough grading" performed by heavy equipment or engineering vehicles such as scrapers and bulldozers.

Motor graders can produce inclined surfaces, to give cant (camber) to roads. In some countries they are used to produce drainage ditches with shallow V-shaped cross-sections on either side of highways.

 Motor graders are commonly used in the construction and maintenance of dirt roads and gravel roads. In the construction of paved roads they are used to prepare the base course to create a wide flat surface for the asphalt to be placed on. Graders are also used to set native soil foundation pads to finish grade prior to the construction of large buildings.

 

 In some locales such as Northern Europe, Canada, and places in the United States, motor graders are often used in municipal and residential snow removal. In scrubland and grassland areas of Australia and Africa, motor graders are often an essential piece of equipment on ranches, large farms, and plantations to make dirt tracks where the absence of rocks and trees means bulldozers are not required.

Capacities range from a blade width of 2.50 to 7.30 m and engines from 93–373 kW (125–500 hp). Certain motor graders can operate multiple attachments, or be used for separate tasks like underground mining.